KVM: selftests: Include sys/mman.h *and* linux/mman.h, via kvm_syscalls.h

Include both linux/mman.h (the kernel provided version) and sys/mman.h (the
libc provided version) throughout KVM selftests, by way of kvm_syscalls.h
(which should have been including sys/mman.h anyways).  Pulling in the
kernel's version fixes compilation errors with the guest_memfd test on
older versions of libc due to a recent commit adding MADV_COLLAPSE testing.

  In file included from include/kvm_util.h:8,
                   from guest_memfd_test.c:21:
  guest_memfd_test.c: In function ‘test_collapse’:
  guest_memfd_test.c:219:47: error: ‘MADV_COLLAPSE’ undeclared (first use in this function); did you mean ‘MADV_COLD’?
      219 |         TEST_ASSERT_EQ(madvise(mem, pmd_size, MADV_COLLAPSE), -1);
          |                                               ^~~~~~~~~~~~~
    include/test_util.h:62:16: note: in definition of macro ‘TEST_ASSERT_EQ’
       62 |         typeof(a) __a = (a);                                            \
          |                ^
    guest_memfd_test.c:219:47: note: each undeclared identifier is reported only once for each function it appears in
      219 |         TEST_ASSERT_EQ(madvise(mem, pmd_size, MADV_COLLAPSE), -1);
          |                                               ^~~~~~~~~~~~~
    include/test_util.h:62:16: note: in definition of macro ‘TEST_ASSERT_EQ’
       62 |         typeof(a) __a = (a);                                            \
          |                ^

Route the includes through kvm_syscalls.h to try and avoid a future game
of whack-a-mole, i.e. so that future expansion of test coverage doesn't run
into the same problem.

To discourage use of sys/mman.h, opportunistically include the kernel's
version of mman.h in test_util.h as it only needs MAP_SHARED, i.e. only
needs the full set of kernel defs, not the libc syscall wrappers.

Fixes: 9830209b4a ("KVM: selftests: Test MADV_COLLAPSE on guest_memfd")
Reported-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Closes: https://lore.kernel.org/all/20260427204313.50741-1-rick.p.edgecombe@intel.com
Link: https://patch.msgid.link/20260428012503.1213654-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

tools/testing/selftests/kvm/access_tracking_perf_test.c

@@ -41,10 +41,10 @@
 #include <inttypes.h>
 #include <limits.h>
 #include <pthread.h>
-#include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 
+#include "kvm_syscalls.h"
 #include "kvm_util.h"
 #include "test_util.h"
 #include "memstress.h"

tools/testing/selftests/kvm/guest_memfd_test.c

@@ -14,10 +14,10 @@
 #include <linux/bitmap.h>
 #include <linux/falloc.h>
 #include <linux/sizes.h>
-#include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 
+#include "kvm_syscalls.h"
 #include "kvm_util.h"
 #include "numaif.h"
 #include "test_util.h"

tools/testing/selftests/kvm/include/kvm_syscalls.h

@@ -2,8 +2,18 @@
 #ifndef SELFTEST_KVM_SYSCALLS_H
 #define SELFTEST_KVM_SYSCALLS_H
 
+/*
+ * Include both the kernel and libc versions of mman.h.  The kernel provides
+ * the most up-to-date flags and definitions, while libc provides the syscall
+ * wrappers tests expect.
+ */
+#include <linux/mman.h>
+
+#include <sys/mman.h>
 #include <sys/syscall.h>
 
+#include <test_util.h>
+
 #define MAP_ARGS0(m,...)
 #define MAP_ARGS1(m,t,a,...) m(t,a)
 #define MAP_ARGS2(m,t,a,...) m(t,a), MAP_ARGS1(m,__VA_ARGS__)

tools/testing/selftests/kvm/include/test_util.h

@@ -19,9 +19,9 @@
 #include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>
-#include <sys/mman.h>
 #include "kselftest.h"
 
+#include <linux/mman.h>
 #include <linux/types.h>
 
 #define msecs_to_usecs(msec)    ((msec) * 1000ULL)

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -5,13 +5,13 @@
  * Copyright (C) 2018, Google LLC.
  */
 #include "test_util.h"
+#include "kvm_syscalls.h"
 #include "kvm_util.h"
 #include "processor.h"
 #include "ucall_common.h"
 
 #include <assert.h>
 #include <sched.h>
-#include <sys/mman.h>
 #include <sys/resource.h>
 #include <sys/types.h>
 #include <sys/stat.h>

tools/testing/selftests/kvm/memslot_perf_test.c

@@ -15,7 +15,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/mman.h>
 #include <time.h>
 #include <unistd.h>
 
@@ -23,6 +22,7 @@
 #include <linux/sizes.h>
 
 #include <test_util.h>
+#include <kvm_syscalls.h>
 #include <kvm_util.h>
 #include <processor.h>
 #include <ucall_common.h>

tools/testing/selftests/kvm/s390/shared_zeropage_test.c

@@ -4,11 +4,10 @@
  *
  * Copyright (C) 2024, Red Hat, Inc.
  */
-#include <sys/mman.h>
-
 #include <linux/fs.h>
 
 #include "test_util.h"
+#include "kvm_syscalls.h"
 #include "kvm_util.h"
 #include "kselftest.h"
 #include "ucall_common.h"

tools/testing/selftests/kvm/s390/tprot.c

@@ -4,8 +4,8 @@
  *
  * Copyright IBM Corp. 2021
  */
-#include <sys/mman.h>
 #include "test_util.h"
+#include "kvm_syscalls.h"
 #include "kvm_util.h"
 #include "kselftest.h"
 #include "ucall_common.h"

tools/testing/selftests/kvm/set_memory_region_test.c

@@ -8,11 +8,11 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/ioctl.h>
-#include <sys/mman.h>
 
 #include <linux/compiler.h>
 
 #include <test_util.h>
+#include <kvm_syscalls.h>
 #include <kvm_util.h>
 #include <processor.h>